This is really strange. I have set the trace in database level and then also in session level. Even after I run a select statement no file is generated in USER_DUMP_DEST! Nor the sql plan is showing up!!!
SQL> show parameter trace

Are you getting confused between setting sql_trace on and setting [url http://docs.oracle.com/cd/E11882_01/server.112/e16604/ch_eight.htm]autotrace on (or 'set autotrace trace explain' judging by the output/behavour described?

This database was rarely used.
I saw that the alert.log for this server was screwed up too. I have fixed that. I wonder if there is any problem in the database itself.
itst50--/oracle/admin/itst50/bdump>> sqlplus /nolog

user6233945 wrote:
This database was rarely used.
I saw that the alert.log for this server was screwed up too. I have fixed that. I wonder if there is any problem in the database itself.
itst50--/oracle/admin/itst50/bdump>> sqlplus /nolog

[oracle@localhost ~]$ oerr ora 980
00980, 00000, "synonym translation is no longer valid"
// *Cause: A synonym did not translate to a legal target object. This
// could happen for one of the following reasons:
// 1. The target schema does not exist.
// 2. The target object does not exist.
// 3. The synonym specifies an incorrect database link.
// 4. The synonym is not versioned but specifies a versioned
// target object.
// *Action: Change the synonym definition so that the synonym points at
// a legal target object.
[oracle@localhost ~]$ oerr sp2 613
00613, 0, "Unable to verify PLAN_TABLE format or existence\n"
// *Cause: An AUTOTRACE command was issued by a user with insufficient
// privileges, or who did not have a PLAN_TABLE.
// *Action: Make sure the user has been granted the PLUSTRACE role,
// and that a PLAN_TABLE has been created for the user.